Soil-Pile-Quay Wall System with Liquefaction-Induced Lateral Spreading: Experimental Investigation, Numerical Simulation, and Global Sensitivity Analysis

Abstract

Extensive damage to offshore and port structures supported on piles behind a quay wall has been frequently reported as a result of soil liquefaction and lateral spreading in earthquakes. This study aims to explore the dynamic behavior of a soil-pile-quay wall (SPQW) system subjected to liquefaction-induced lateral spreading in terms of experimental investigation, numerical simulation, and global sensitivity analysis (GSA). A large-scale (1g) shake-table experiment on a SPQW system is presented in detail, including sensor arrangement, model configuration, and experimental results. Typical liquefaction phenomena, such as sand boils and ground settlement, were observed during the test. The shake-table experiment results were used to validate a three-dimensional (3D) nonlinear finite-element (FE) model developed for dynamic analysis of a fully coupled soil-water system. This FE model accounts for the interactions of the soil, pile, and quay wall through explicitly modeling them as an integrated system. Based on the validated FE model, a GSA was performed to further investigate how variations in system properties influence the dynamic responses of the SPQW system. The GSA with high computational efficiency was implemented using the polynomial chaos expansion (PCE) surrogate model, and the GSA results indicate the relative importance of modeling parameters, which provides insightful information about the system behavior. The presented work provides useful guidance on experimental and numerical simulations of typical SPQW system.